Brassiere frame



April 1955 M. SCHWARTZ 2,705,800

BRASSIERE FRAME Filed Oct. 20, 1954 FIGVZ lNVENTOR Marcus SchwanzATTORNEY United States Patent BRASSIERE FRAME Marcus Schwartz, Flushing,N. assignor to S. & S. Industries, Inc., New York, N. Y., a corporationApplication October 20, 1954, Serial No. 463,386

1 Claim. (Cl. 2-42) This invention relates to wire frames forbrassieres.

Broadly, it is an object of the invention to provide an arcuate wire ofsubstantially rectangular cross-section for use in a brassiere beneaththe breast pockets for supporting the breasts.

With the advent of the strapless brassiere a means of support wasnecessary, since the brassiere was no longer supported by shoulderstraps. The only successful method of supporting the brassiere was theuse of arcuate wires. Presently, the brassiereis supported by the use oftwo arcuate wires of round cross-section beneath the breast pockets andsupporting each breast, much on a suspension bridge principle, whereby abridge is supported at both ends and properly engineered so that eventhough the span may be great and the weight which is carried is veryheavy, the center can sufliciently support any given load. These arcuatewires, to function properly, must be of suflicient round cross-sectionas to withstand the pull of the weight of the individual bust. As can bereadily seen, the weight of the bust of a large woman would necessitatethe use of a Wire with a heavier round cross-section than the weight ofa bust of a Woman which is small by size and weight. However, since themanufacturing of brassieres and of the arcuate wires of the roundcross-section is a mass production item, it does not lend itself to theindividual fitting of a diflerent thickness of a round crosssection foreach particular weight by bust size. Therefore, one thickness of roundcross-section arcuate wire has been developed, which does an adequatejob for all sizes. Since this arcuate wire of round cross-section mustbe of sufficient rigidity to produce the required support in thevertical direction, it is also comparatively rigid in the transversedirection because in a wire with a round crosssection, the rigidity ofthe wire is the same in any direction. Heretofore, arcuate wires ofround cross-section have been used in brassieres, but such wires haveproven unsatisfacory, since an excess amount of pressure was exertedagainst the body in a transverse direction, that is, at right angles tothe radii of the wire curvature. Wires for use in brassieres, tofunction properly, and withstand undue pressure against the body of thewearer, must be of sufhcient rigidity to produce the required support inthe vertical direction, have a certain degree of flexibility in thevertical direction and have a greater flexibility and resiliency in thetransverse direction, that is, to the plane of the curved wire. If acurved Wire of round crosssection is sufliciently resilient in thelateral direction, its use in brassieres is not sufficiently rigid inthe vertical direction to properly support the bust when worn.

Being very conscious of the undue pressure against the womans body,which is caused by the rigidity of the wire, I have been trying for manmany months to find a solution. I have conducted many experiments withthe padding of brassieres with foam rubber, where the pressure of thewirev is located. After a great many experiments, I finally arrived atthe answer. A wire must be developed which would have sufiicientrigidity in the longitudinal plane to take care of every size and yethave good flexibility in the transverse direction, so as to have littleor no pressure against the body. By taking a special type ofhypereutectoid steel wire of between .80 and 1.05 carbon content andtreating it as hereinafter described, such wire has the proper rigidityand flexibility in the vertical direction and the desired degree offlexibility in the lateral direction, that is, the degree of flexibilityin the lateral direction is greater than in the vertical direction. Whenthis wire is used as a brassiere support beneath the breast, it willperform its required and proper function without undue pressure againstthe body of the wearer.

For a fuller understanding of the nature and objects of the invention,reference is had to the following detailed description in connectionwith the accompanying drawings, in which:

Fig. 1 is a plan view of one of a pair of brassiere wires comprising theframework of a brassiere; and

Fig. 2 is an enlarged sectional View taken along line 2-2 of Fig. 1.

Referring to the drawings, numeral 10 represents one of a pair of wirescomprising a supporting frame for a brassiere. A special type of roundcross-section hypereutectoid steel is selected for the manufacture of asubstantially rectangular cross-sectional member for a brassiere frameand such steel member undergoes certain operations during its processingto change the inherent grain structure in order to produce the desireddegree of flexibility and resilience. This steel member, in its annealedcondition, has a crystal structure containing free ferrite and pearlite.The ferrite shows up as white areas surrounding the pearlite on polishedand etched specimens. Under one hundred magnifications with amicroscope, the structure shows equiaxed polyhedral grains.

This special wire, after further reduction of diameter, has anoverlapping of the elongated grains which adds considerably to thestrength of the wire material. The wire has a high tensile strength andhigh hardness due to the reduction of area caused by the wire drawingoperations and is now in condition for further processing.

Further drawing operations of this wire causes a lengthening of thegrain and a large amount of residual stress which is then relieved by aspecial operation consisting of a thermal treatment suflicient to refinethe grain structure of the wire member and also prepare the wire memberfor additional drawings, which cause a more uniform sorbitic structurewith a fine dispersion of ferrite.

The round wire is now ready for a special sequence of operations to makeit a substantially rectangular crosssectional shape with round edges, asshown in Fig. 2, which is the desired shape for use in brassieres. Weeither flatten the round wire into cross-sections of rectangular shapewith round edges, or into other shapes, by passing it through a rollingmill, flattening it in a power press or in a drop hammer. This can bedone in two ways, that is, either in a continous coil or out intoindividual pieces of predetermined length. I have also produced a wireframe for brassieres and began with a flat Wire of the desired thicknessfrom a continuous coil. This flat wire was then cut to the desiredlength, and then curved to the desired curve of arc, as shown in Fi 1,and as figured by the modulus of elasticity of material.

The other method of fabricating this wire is to have the round wire cutto the desired length'and then formed into an arcuate shape, as shown inFig. 1, by bending the wire beyond its elastic limit, by previouslydetermining the modulus of elasticity of the wire, which permits acertain amount of spring-back to occur. During this curving the grainsactually slide over one another an infinitesimal amount Withoutdestroying the bond of the amorphous cement holding them together. Thisover straining of the wire causes the grains to be compressed on theinside of the curve and elongated on the outside, thereby inducingadditional residual stresses in the wire and causing it to be in anunstable condition. It now requires careful handling to prevent changingthe desired shape until .astress equalizing heat treatment is provided,The wire is then baked for about one-half hour at temperature between300 F. and 500 F. to stress relieve it. A certain amount of spring-backwhich occurs during stress relieving is allowed for during themanufacture. The sharp edges of the ends of the wire are taken care ofby either the forming of spherical terminals, or the placing of arounded part upon each end.

The round wire is then flattened into a rectangular shaped cross-sectionwith rounded edges, as shown in Fig. 2, or into other shapes either bypassing it through a rolling mill, flattening it in a power press, ordrop hammer, forcing the grains to become more closely packed therebyreducing some of the bending stresses by reorienting the structure.This, however, sets up additional stresses due to the cold work ofpressing. Th s cold working realigns the grains into the desirablecondition for additional strength and higher hardness thereby permittinggreater resilience. This is also due in part to the change in shape ofthe section in the transverse plane and this combination of effectsimparts the desired mechanical properties. The unstable condition causedby residual stresses within the structure from cold working are thenrelieved by a low temperature thermal treatment, as hereinbefore stated.The special sequence of operations needed to produce the correct type ofwire for the purpose described, combined with the unique formingoperations and thermal treatments, permit manufacture of a product witha combination of flexibility and resilience heretofore unavailable andnovel for use in brassiere framework;

The wire is treated so as to be completely rust-resistent. It may beelectro-plated, metallic coated, or receive a baked enamel finish toprovide a smooth finish coating. 1

Load and deflection tests were made to determine the flexibility andresilience of round sections of wire versus rectangular shaped wire, andsuch tests were conducted on a precision testing instrument commonlyused for such tests in the following manner. In'making the longitudinaltest, a brassiere wire frame of standard type round cross-section wasplaced on the hooks of a spring testing instrument and extended .625 inwhich condition it exerted a load of 28 ounces. A rectangular sectionwas then placed on the same hooks (after removing the round sectionframe) and also extended .625" in which condition it exerted a load of28 ounces. The loads exerted are exactly the same. The load placed uponthe round Wire was exerted along the axis of the arc and it tended tofurther open the arc to the point of extension amounting to .625". Thisis the amount of extension required to fit the wire around the breast ofthe wearer.

Inasmuch as the stress. caused by the extension was less than theelastic limit for both sections, the frames returned to their normalfree position. With this amount of deflection in both instances therewas no distortion or twisting of either wire.

With the spreading of the brassiere wire to acccommodate fitting aroundthe breast of the wearer, it is obvious that the pressure exerted by thewire when released or collapsed will be equal to the pressure requiredto open the wire. The rectangular cross-sectional wire will thereforehave the same resistance of stretch and will free end. The loads areshown in the following table.

Round Wire, Flat Wire, Deflection Ounces Ounces (The round wire took aslight permanent set at 1% deflection indicating thesafe maximumdeflection had been reached.)

The conclusion shown revealed that while both sections have the samelongitudinal loads, a tremendous difference occurs in the transversetests asshown in the above table.

The flat wire did not take a set even at-2 of deflection and could havebeen deflected more if desired.

It was found that 2" of lateral deflections was the maximum required tocause the rectangular cross-sectional Wire to fit a wide range offigures.

' before or after it is'curved.

The round and rectangular section ratio is 28 divided by 1.9 and equals14.75, at /8" deflection in both planes. The ratio of the two wiresections is 64 divided by 4.8 and equals 13.3, for a transversedeflection of 1 For other conditions it varies between 12.5 to 14.2.

The conclusion with respect to the ratio of loads in the transverseplane shows the round wire to be quite stiff laterally. The round wireexerts about 13 times as much load against the body as does the flatwire. The flat wire, because of its greater flexibility (or lessrigidity) requires only 7 /2% of the load to deflect it laterally, thandoes the round wire.

With respect to the flexibility of the round wire in comparison to therectangular wire of my structure, the ability to be deflected in thelongitudinal direction, parallel to the direction of the wire, for bothround and rectangular sections is the same. This desired result isaccomplished by correctly determining the size of the rectangular shapewith respect to the round shape in such manner that the section modulusabout the neutral bending axis is the same for both sections.

The increased ability for the rectangular section to be flexible in thetransverse plane at a direction at right angles to the longitudinaldirection is accomplished by the unique shaping of the rectangular wireso that the section modulus about the neutral bending axis in this planeis of a different value than it is about the other axis. The sectionmodulus of the round section, however, is the same in both planes,therefore the flexibility in the transverse plane is not improved.

With respect to the resilience of the round wire in comparison to myrectangular wire structure, the ability to spring back to the originalfree position after deflection is the same for both round andrectangular sections when the deflection is in the longitudinal plane, acondition that can be easily made to exist by the proper temper orhardness placed in each material.

In the transverse plane of bending, however, a large difference inresilience exists between the round and rectangular sections. Therectangular section can be deflected much further than the round sectionand return to the normal free position without permanent set. Thisoccurs because the change in shape changes the section modulus therebylessening the fibre stress during deflection and permitting moreresilience in this transbending direction. This desired condition cannotbe obtained with a round section because the section modulus is the samein both planes.

The amount of temper is related to the hardness and tensile strength.The desired temper of the flattened section, to bring the elastic limitto the correct value for proper flexibility and resilience isaccomplished by a correct determination of hardness in the wire beforeforming it into an arcuate shape, which is determined by the amount ofcold work done in the flattening process and by a low temperaturethermal treatment. The control of these operations can bring about thedesired properties and temper. The proper amount of temper needed hasbeen determined by actual test and is regulated by quality controlmethods verified by Rockwell Hardness Tests to maintain the propercondition. By actual tests, on sample parts and from records made, thehardness that provides the proper mechanical properties of tensilestrength, temper, resilience and flexibility is. Rockwell C42C49.

When a pair of such wires are used or positioned into a slotted sectionof a brassiere, dress or undergarment, such as a brassiere slip, it isfound to have ust the proper amount of lateral and vertical flexibilityand vertical and lateral rigidity. Such wires provide the correctvertical support for the breasts and the proper resiliency andflexibility laterally so that there are no undue pressures against thebody of the wearer and the brass iere can be worn comfortably the entireday and evening.

It is possible to form the thickness of the wire, either It is alsodesirable that the opposed longitudinal edges of the wire remainslightly curved for greater comfort to the wearer.

While I have described the cross-section of my wire as substantiallyrectangular, it is within the scope and spirit of the invention to haveother cross-sections, such as oval, in the form of the figure 8, doubleconcave, or other similar cross-sections, so ion as the arcuate wire issubstantially rigid in its longitudinal plane andhas greater flexibilitylaterally than in its longitudinal plane.

I claim: a l I Asubstantially rigid arcuate wire brassiere frame ofhypereutectoid steel of substantially rectangular cross section havingits longer dimension extending radially of the curve, and having agreater degree of lateral flexibility than longitudinal extensibility,said lateral flexi 'lity being approximately fourteen times the lateralfiexi t ity of a round wire of the same cross sectional area under thesame load and having the same longitudinal extensibility as the roundwire, permitting lateral deflection of the Wire from the unstressedplane of the Wire to fit the contours of the body of the wearer With- 105 out causing a torsional twisting of the wire along the curve of thearc.

Reierenees Cited in the file of this patent UNITED STATES PATENTS145,285 Dudley Dec. 9, 1873 1,989,303 Alberts Jan. 29, 1935 2,527,521Bloom ct. 31, 1950

